This invention is directed to a method of bonding the entry ends of a plurality of discrete wires to form a unitary ribbon cable for insertion into and termination by an electrical connector, such as a modular plug. While the invention has diverse application for the preparation of wires to be terminated within a connector, it has particular utility with the loading of modular plugs which often must be terminated in the field by technicians, or in small factory operations manually. A first approach introduced several years ago was the use of a load bar insert, or wire organizer, where the discrete wires were first loaded into such load bar insert to align and position the wires for eventual entry into the connector. However, problems still persisted with the use of such inserts, as free ends of the wires still had to be directed to an assigned passageway in the connector, and stubbing of the end could result.
While the application of this invention is broad, for convenience, the further description will be directed to the field of modular plugs, a product well known in the art, and the applicability of the invention hereof as it relates to the loading of a modular plug. Modular plugs, a relatively inexpensive electrical connector, are used extensively in telephonic and other data communication systems. Frequently such plugs must be terminated in the field by technicians, or in a factory by assemblers fabricating patch cords. Typically the cable to be terminated in the plug is a bundle of four twisted pair, insulated, multi-colored wires (eight in total), within a cable jacket or wrap of an insulating sheath. The bundle may optionally include a surrounding shield or a drain wire for use in a shielded plug. In any case, to prepare the cable for eventual termination in the plug, the cable jacket is peeled back to expose the various insulated pairs. Thereafter, with the several insulated wires exposed, the wires are untwisted and arranged in the desired order, generally in a side-by-side fashion. The wires are then individually inserted into the connector housing and terminated by an insulation piercing blade, a termination procedure known in the art. Recognizing these cumbersome procedures, load bar inserts were developed to facilitate the loading process. A typical loading bar insert is illustrated in U.S. Pat. No. 4,713,023. The invention thereof includes a wire positioning means for holding insulated conductors in an array so that the ends thereof are presented in alignment below terminal receiving cavities when the wire loaded positioning means is in the housing. The positioning means includes cam means formed thereon and adapted to engage a housing strain relief section when it is moved downwardly, whereby the positioning means is moved forwardly in the housing to fully seat the positioning means therein and position the free ends of the insulated conductors below the terminals.
In UK Patent Application NO. 2 249 222A, assigned to the assignee hereof, there is taught an electrical connector and insert therefor, where the invention relates to a plastic insert for such connector and has a row of wire guiding mouths each for guiding an individual wire into a passageway as the cable is inserted into the connector. The cable has at least one wire less than the number of the passageways and the insert has at least one solid blanking-off portion for blanking off the single or plural unused passageways. The wire guiding mouths of the insert are defined by at least one longitudinal opening having scalloped longitudinal edges.
U.S. Pat. No. 4,601,530, assigned to the assignee hereof, teaches a preloaded wire organizer for a modular type plug. Specifically, the patent teaches the process of preloading wires into a wire holder which locates the leading ends of the wires at the same pitch as passageways in the connector housing. The wire holder, supported by the wires, is then inserted into and along a mouth of the housing until it abuts a tapered throat at the entrance to the passageways. Further advance of the bundle feeds the discrete wires through the wire holder into the respective passageways guided by the throat, while the wire holder remains adjacent the tapered throat.
In a recent development that utilizes a load bar insert for use with a modular plug, while offering improved performance at Category 5 levels, a performance level known in the art, was introduced by Stewart Connector Systems, Inc. of Glen Rock, Pa. They introduced a Category 5 performing modular plug utilizing a sliding wire management bar, where such bar contains two rows, each with four through holes, to receive the standard eight wires of a cable. To use the management bar, the user is advised to arrange the wires in two equal sets, and cut each set of four at a 45.degree. angle such that no two wires are of the same length. With the prepared wires, the wires are individually fed into the holes of the wire organizer, in sliding engagement therewith, then trimmed to the same length. For the loading step, the wire organizer is first pushed to the end of the trimmed wires, then inserted into the connector housing. In the fashion of U.S. Pat. No. 4,601,530, when the wire organizer can no longer move forward, the wires are pushed beyond the wire organizer into a position to be individually terminated, as known in the art. While claiming to provide Category 5 performance, the assembly and termination of the modular plug is very labor intensive.
In a companion patent application, filed concurrently with this application by one of the inventors hereof, where such companion application was assigned U.S. Ser. No. (Attorney Docket 16012), an improved load bar insert is disclosed. The invention thereof, where the application is incorporated herein in its entirety, relates to an electrical connector, preferably a modular plug. A preferred embodiment of the invention of said companion application comprises a dielectric housing having a conductor receiving end, a conductor terminating end, a passageway communicating internally between the respective ends, and a spacing insert in the passageway to receive a plurality of conductors and to position same in a manner to achieve Category 5 performance levels in the modular plug. The insert is characterized by having an upper surface and a lower surface to receive or position selected pairs of the conductors. Within the limits of the housing, the insert maximizes the separation of the selected pairs and arranges them in plural planes before being realigned into a common plane for termination at the conductor terminating end. A first embodiment includes grooves in the upper and lower surfaces of the insert, while a second embodiment is directed to a rod like member, such as may be made of an elastomer, styrofoam, or plastic tube. A feature of this companion invention is the provision of separating the wires into plural planes, then bringing them together for loading into the modular plug. By incorporating the method of this invention, improved performance levels are ensured in a timely and cost efficient manner.
The procedure by which this invention supports the performance and loading of the modular plug of the companion application, and its ability to generally improve the speed in which modular plugs may be factory terminated, will become apparent in the description which follows, particularly when read in conjunction with the accompanying drawings.